Alloy and method



liatented Nov. 3, 1925.

a'ruir FREDERICK W. KAR-ITZK Y, OF GABVJOOD, NEVZ JERSEY, ASSIGNOE T0 HENRY E. NEWHALL, OF PLAINFIELD, NEW JERSEY.

ALLOY AND METHOD.

N0 Drawing.

To (/77 IIf/lO/Ilit may concern lle it known that l. FKI'IYHLKHK liuu'rmn', a citizen of the United States, residing at Garwood, in the county of linion and State of New Jersey, have made certain new and useful Improvements in Alloys and Methods, of which the following a s 'icciiication.

My invent-ion relates to an alloy and the method of making it.

My invention f1lll'll(1 l(lilt(8 to an alloy of zinc, aluminum and tin, which can he cast in n'iet-al molds, and also in sand molds, at reasonable casting temperatures, the result ing casting-heingstrong and rigid and there being no material luenltage duei'o shrinkage in the mold. p i

Care must be exercised that the alloy will not shrink to'a material extent in the mold for this would result in breaking the casting in the mold. The melting point of the alloy must not-[he too high, for with a high melting point the alloy cannot be satisfactory poured 'intothe mold, The ingredients must be so proportioned that the resulting casting will not be too brittle. which would result in a weak casting. The ingredients must also be soproportioned that the resulting casting will be rigid ,and strong.

The meltingpoint of commercial aluminum is 1200 degrees Fahrenheit; the melting point of zinc is 785 degrees'Fahrenheit, and the melting point of tin is 446} degrees Fahrenheit.

I have found in practice that I can obtain a strong, rigid perfect casting, by employing an allo of zinc, 10% alumi nnm and 5% tin, which can .be poured at about 750 F. to 800 F.. the preferred temperature being, about 775 F. The pouring temperature may be run up to about 850 F. but this temperature is greater than necessary. I If the temperature is too great the overheating will spoil the metal, and, further, the alloy will not run in the mold.

Castings so made run full to the mold, are strong and rigid and there is no breakage due to shrinkage in the mold. The melting point of this alloy can be reduced by increasing the percentage of tin and decreasing the percentage of zinc and alarm- Application filed December 31. 1924. Serial No. 758,974.

num and still a good strong casting will result.

llhile l havev given the percentages of zinc. alumii'nun and tin which E preferably employ, it of course to be understood these are merely illustrative and that my invention is not to be confined to such perccntages.

The alloy should be made by the following fill method or steps:

The zinc and aluminum are separately melted in separate crucibles or containeis Then the molten aluminum is poured into the molten. zinc and. stirred thoroughly.

Then the molten tin is poured into the comhined molten a ine and aluminum and stirred. Among other advantages of this method is that dressing is reduced to a. minimum.

Having thus described this invention in connection with illustrative embodiments tl'ierco't, to the details of which I do not desire to be limited, What is claimed as new and what is desired to secure by Letters Patent is set forth in the appended claims. W

What I claim is:

1; An alloy comprising about 85% of zinc. 1072- 01 aluminum and of tin. i

A new article of manufacture comprising a strong, rigid and true casting formed 80 of zinc, aluminum and tin, the casting containing about of zinc, about 10% of aluminum and about 5% of tin.

3. The method of manufacturing an alloy v of zinc, aluminui'i'i and tin consisting in S5 melting the zinc and aluminum separately then pouring one into the other, and then pouring the molten tin into the mixed alumlnum and zinc.

4. The method of nmmi'fact-uring an alloy 9.0.

molten tin into the mixed molten Zinc and aluminum.

5. A metallic alloy lidapted for casting.

having the characteristics of not shrinking to a material extent in a mold and making a strong, rigid and perfect casting besides 0 being tough and homogeneous, consisting of zinc in largely predominating amount and containing aluminum and tineach in substanti-al amounts and centaining no substantial; ambunt of other elements.

6; "A metallic alloy adapted for casting,

' having the characteristics of not slfrinking to mmateirial extentin a mold and making a,

sill-(311g; rigid and perfect casting besides being tough and llomogemeous and having a relatively low melting point consisting of zinc in largely predominating amout and containing alumilimn and bin each in substantial amounts and containing no substam tial amoun; of other elemnt-s.

FREDERICK 1V; KARITZKY. 

